Currently, various portable mobile terminals become more and more popular. A guardian usually has to equip a ward with a mobile terminal, e.g., a cell phone, so as to conveniently keep touch with the ward who may be a minor, an unconscious aged or any other people unable to make judgment independently. When needing to know the ward's situation or being eager to contact the ward, the guardian has no choice but to call or send a short message to the ward on his own initiative, and sometimes has to do so for so many times. So it is troublesome for the guardian to monitor the ward's use of the mobile terminal.
In addition, the guardian wants the ward to be honest when he makes a phone call or sends a short message to the ward to learn the ward's condition, but quite often things will not turn out the way he wished. For example, parents want to know if their child is playing a game, but usually they cannot get the veracious information from the child by calling him, and cannot remotely control the game function of the portable device of the child. In addition, once one of the following situations occurs, such as the mobile terminal not being in the service area, or having been switched off, or being lack of power supply, usually the guardian cannot learn such situations in advance and will fail to reach the ward, and can not perform the guardianship effectively.
Currently, in order to locate a ward in real time, the ward can be equipped with a Global positioning system (GPS) terminal device, with which the ward can be precisely located. This mechanism can provide a guardianship function, however owing to the high price and too much service charge, the OPS terminal device is not suited for ordinary people and is difficult to be popularized.